Slide fastener gapping machine

ABSTRACT

A machine for punching out interlocked teeth carried on adjacent edges of a pair of tapes of a continuous slide fastener chain to provide in the latter gaps free of teeth. The machine comprises die means adapted to receive on an upper surface thereof a portion of the slide fastener chain to be gapped, punch means cooperating with the die means for punching out interlocked teeth for forming a gap free of teeth in the slide fastener chain, and means for automatically adjusting the position of the slide fastener chain in longitudinal direction relative to the punch means so that the teeth on opposite ends of the gap will be fully cut through without damage to each next adjacent tooth remaining on the slide fastener chain.

[ 51 Aug. 27, 1974 United States Patent [191' Perlman SLIDE FASTENER GAPPING MACHINE [75] Inventor: Morris Perlman, Brooklyn, NY. Primary Examiner Meister [73] Assignee: Carbide Form Grinding Inc.,

Attorney, Agent, or FirmMichael S. Striker Brooklyn, NY.

ABSTRACT A machine for punching out interlocked teeth carried on adjacent edges of a pair of tapes of a continuous slide fastener chain to provide in the latter gaps free of teeth. The machine comprises die means adapted to receive on an upper surface thereof a portion of the slide fastener chain to be gapped, punch means cooperating with the die means for punching out interlocked teeth for forming a gap free of teeth in the slide fastener chain, and means forautomatically adjusting the position of the slidefastener chain in longitudinal direction relative to the punch means so that the teeth on opposite ends of the gap will be fully cut through without damage to each next adjacent tooth remaining on the slide fastener chain.

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UNITED STATES PATENTS 3,190,161 6/1965 Runnels et 83/921 x 10 Claims, 10 Drawing Figures SIJIDE FASTENER GAPPING MACHINE CROSS-REFERENCE TO RELATED APPLICATIONS BACKGROUND OF THE INVENTION In the manufacture of individual slide fasteners it is common practice to produce a first a continuous slide fastener chain composed of a pair of tapes carrying on adjacent edges thereof interlocked coupling elements or teeth. This continuous slide fastener chain is then provided with longitudinally spaced gaps free of coupling elements, and subsequently thereto the other components for forming finished slide fasteners,rsuch as bottom stops, sliders and top stops are attached to the chain, preferably while the latter is stilled in continuous form. Finally, the chain is cut between the ends of each gap into individual slide fasteners.

The present invention relates to a machine for providing gaps free of teeth or coupling elements in a continuous slide fastener chain.

SUMMARY OF THE INVENTION It is an object of the present invention to provide for a gapping machine of the aforementioned kind which is constructed in such a manner that the teeth at opposite ends of each gap which have to be removed are fully cut through without causing damage to the next adjacent tooth which has to remain on the chain at opposite ends of the gap.

It is a further object of the present invention to provide a gapping machine of the aforementioned kind in which the useful life of the machine, especially of the die thereof is increased in an advantageous manner.

It is an additional object of the present invention to provide a gapping machine of the aforementioned kind which is composed of relatively few and rugged parts so that the gapping machine may be manufactured at reasonable cost and will stand up properly during extended use.

With these and other objects in view, which will become apparent as the description proceeds, the machine according to the present invention for punching out interlocked teeth carried on adjacent edges of a pair of tapes of a continuous slide fastener chain to provide in the latter gaps free of teeth, mainly comprises die means having an upper surface, punch means arranged above this upper surface of the die means and including a pressure pad formed with a slot therethrough and a blade-shaped punch extending through this slot. The pressure pad and the punch being movable relative to each other and toward and away from the die means in such a manner that during movement of the pressure pad and said punch towards the die means the slide fastener chain portion on the upper surface of the die means will be clamped on the latter whereafter the punch will punch out interlocked teeth from the chain to form a gap therein. The machine includes further means carried by the pressure pad for aligning longitudinally the teeth on the chain relative to the punch so that the punch will punch out complete teeth on opposite ends of the gap without damaging adjacent teeth remaining on the slide fastener chain.

The machine preferably includes also a punch holder block carrying the punch and being arranged above the pressure pad, means connecting the punch holder block and the pressure pad for limited movement relative to each other in the direction toward and away from the die means and biassing means for biassing the pressure pad away from the punch holder block and towards the die means. The aligning means is arranged adjacent one end edge of the punch for aligning the side face of one tooth with this end edge when the pressure pad engages the chain portion on the die means.

The aligning means preferably comprises a bar carrying at the lower end a finger of a width substantially equal to the space between two adjacent teeth on one tape of the slide fastener chain, means mounting the bar on the pressure pad movable in a direction inclined to the vertical with the upper end of the bar further spaced from the end edge of the punch than the lower end thereof, means biassing the bar relative to the pressure pad towards the upper surface of the die means, and means limiting the downward movement of the bar relative to the pressure pad.

The die means preferably comprises a pair of spaced apart die blocks and a pair of elongated straight inserts of square cross-section releasably secured to the die blocks to partly overlap .the space between the spaced apart blocks in such a manner that opposite side faces of the inserts are spaced from each other a distance substantially equal to the width of the punch so that the upper edges of the opposite side faces of the inserts form cutting edges cooperating with the punch for punching out teeth on the slide fastener chain during movement of the punch beyond the cutting edges, whereby when the cutting edges are worn, fresh cutting edges may be presented by turning each of the inserts through each time. The length of each insert is preferably at least twice the length of the punch so that each of the inserts may also be turned end-to-end and then again be turned through 90 each time when one of the cutting edges is worn so that a total of eight cutting edges may be presented to the punch.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of a gapping machine according to the present invention;

FIG. 2 is a perspective view of the die shown partly in exploded position;

FIG. 3 is a perspective view of the die shown in FIG. 2 and illustrating also further components of the machine cooperating with the die;

FIG. 4 is a cross-sectional view through part of the machine taken along line IV-IV of FIG. 5;

FIG. 5 is a cross-sectional view taken along V-V of FIG. 4;

FIG. 6 is a side elevation as viewed in the direction of the arrows 6-6 of FIG. 4;

FIG. 7 is a cross-sectional view similar to FIG. 4-and showing only components thereof which are related to the aligning means of the machine, this Figure showing the aligning means in the initial position of an operating cycle;

FIG. 8 is a view similar to FIG. 7 and showing the aligning means in a subsequent position;

FIG. 9 is a view similar to FIG. 8 and showing the aligning means in the end position during the cutting operation; and

FIG. 10 is a fragmentary plan view of a slide fastener chain showing a gap therein as viewed in line 10-10 of FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing in detail, it will be seen that the gapping machine according to the present invention mainly comprises die means 28 mounted on a fixed support 22, for instance the bolster plate of a power press of standard construction, and punch means 30 above the die means reciprocable toward and away from the latter by being for instance connected in a manner known in the art to the reciprocating ram of the power press, not shown in the drawing. A continuous slide fastener chain 32 is fed for instance from a reel 34 turnably mounted on a spindle 36 secured in any convenient manner to the frame of the aforementioned power press, though a loop 38, through a tension unit 40 comprising rotating rollers 42, 44 and 46, and in horizontal direction over the upper surface of the die means 28 between the punch and die means.

The continuous slide fastener chain 32 (FIG. 10) comprises a pair of tapes 48 having adjacent side edges 50 and provided on each of the side edges with a row of interlocking slide fastener teeth 52.

The die means 28 preferably comprise a base plate 24 secured by bolts or the like to the support 22 and a die unit 26 secured by bolts or dowel pins, not shown in the drawing, to the plate 24. The die unit 26 comprises a pair of die blocks 54 with spacers 58 sandwiched between adjacent faces of the die blocks 54 at opposite ends of the latter to form between opposite faces of the die blocks 54 an elongated space 56. The blocks 54 and the spacers 58 therebetween are secured together into a single unit by bolts 60. An elongated, straight insert 62 of hardened steel or carbide and of square cross-section is placed upon each die block 54 in such a manner that each insert overlaps in part the space 56, and the inserts are firmly secured in position by holding plates 64 which in turn are secured by screws 66 to the blocks 54.

The punch means 30 preferably comprise a blockshaped punch holder 80 formed with a central slot 86 extending from the bottom face of the holder 80 upwardly in the latter and a blade-shaped punch 78 arranged with the upper portion thereof in this slot and held therein in fixed position by a plurality of set screws 90 screwed into transverse bores extending through the punch holder block 80 and engaging one side face of the portions of the punch 78 in the slot 86, and an additional set screw 88 abutting with an end thereof against an end edge of the punch 78. The punch holder 80 is guided for movement in vertical direction toward and away from the die means 28 on a pair of guide posts 84 projecting vertically upwardly from the base plate 24 through bores 82 in the punch holder block 80 as that the punch holder block 80 and the punch 78 carried thereby is reciprocable in vertical direction towards and away from the die means 28. The punch means includes further a pressure pad 72 arranged between the punch holder and the die means 28 and connected to the punch holder 80 for limited movement relative thereto in the direction toward and away from the die means. The means connecting the pressure pad 72 and the punch holder 80 to each other preferably comprise four pins 92, the lower end portions of which extend with a tight fit through corresponding vertical bores formed in the pressure pad 72 and the lower portions of the pins 92 are secured in the bores of the pressure pad 72 by a plurality of transversely extending set screws 94 screwed into corresponding bores of the pressure pad 72 and engaging with ends thereof the lower end portions of the pins 92. The upper portions of the pins 92 extend with a slide fit through corresponding bores in the punch holder block 80 and each of the pins 92 has a head 96 at the upper end thereof movable in a portion of enlarged diameter of each bore in the punch holder 80. Biasing means in form of compression springs 98 are provided between the pressure pad 72 and the punch holder block 80 for normally holding these two components apart. The biasing means preferably comprise compression springs 98 and located preferably with opposite ends in counterbores of the pressure pad and the punch holder block. The pressure pad is preferably provided with a pair of projections 74 to opposite sides of slot 76 therein and adapted to engage, when the pressure pad is moved in downward direction, the tapes 48 of a slide fastener chain portion resting on the upper surface of the die means. The die unit 26 preferably further comprises a pair of guide plates 68 and 70 secured in any convenient manner to the outer faces of the die blocks 54 and projecting upwardly therefrom for guiding the pressure pad 72 for movement in vertical direction.

According to the present invention the pressure pad 72 also includes aligning means 100 shown in operative positions in FIGS. 7-9. The aligning means 100 comprise a passage 102 formed through a left end portion, as viwed in FIGS. 4 and 7-9, of the pressure pad 72 and extending inclined to the vertical with the upper end of this passage spaced further from the left end edge of the punch 78 than the lower end thereof, a bar 104 fitted in the passage 102 to be slidably guided therein and having at the lower end thereof a finger 112 projecting downwardly beyond the pressure pad and having a width substantially equal to the space between two adjacent teeth 52 on one tape 48 of the slide fastener chain. The bar is formed with a longitudinally extending elongated slot 106 having opposite closed ends, and a pin 6 forward to the pressure pad extends transversely through the slot in the region of one of the ends, for limiting downward movement of the bar relative to the pressure pad. Biasing means in form of a coil compression spring 110 are provided bearing with one end thereof against the pin 108 and with the other end against the lower closed end of the slots 106 so as to normally urge the bar 104 in downward direction.

The machine includes further guide bars 116 and 118 respectively positioned over opposite ends of the die unit 26, each guide bar having in the region of one end projections 120 on the underside thereof, between which the teeth 52 on the slide fastener chain travel across the die unit 26. Each bar 116 and 118 is pivotable about a fulcrum screw 122 respectively mounted in opposite ends of the vertical plate 68. An end of each guide bar has an opening 124 for freely receiving a screw 126 projecting upwardly from the plate 24. A compression coil spring 128 around each screw 126 normally urges the associated end of the bar upwardly so as to cause the other end of the bar to bear downwardly, thus securely retaining the slide fastener teeth between the projections 120.

The guide bars 118 has an upwardly extending shield 130 integral therewith, as shown in F168. 4, 5 and 6, for the purpose of deflecting any dipped off teethlcluring machine operation and thus preventing dipped'off teeth fragments from" lodging upon the slide fastener chain after the chain leaves the machine The guide bar 118 also includes a spring steel rod 13,2

extending therefrom, as shown in FIG. 6, the rod being located to bear frict'ional'ly against the upper side of the slide fa'sternr chain 32, so astopipk off any cut tooth fragments still imbedded in the chain tapes and for scraping off these fragments from the tapes. Another rod 134 secured to the guide plate 70 bears againstthe underside of the slide fastener chain for the same purpose.

The above-described machine will operate as follows:

The slide fastener chain is pulled intermittingly in longitudinal direction through the machine by pulling means of standard construction, not shown in the drawing, and engaging the slide fastener chain to the left of the machine 20, as viewed in FIG. 1. As mentioned before, the punch and die means may be mounted in a standard power press, so that the ram of the power press connected to the punch holder 80 of the punch means moves the latter toward and away from the die means 28, and the pulling means are coordinated with the reciprocation of the punch means in such a manner that the chain travel is halted an instant moment before the punch moves downwardly. As the pressure pad 72 moves downwardly together with the punch 78, the aligning means 100 will reach successive positions as shown in FlGS. 7-9.

Although the entire cycle of this operation occurs within a fraction of one second, it is best to break this cycleof operation into component instances to identify the progressive movement of the machine.

The chain advance may be stopped at any imprecise position of the chain 32 relative to the punch 78, so that when the pressure pad 72 starts to move downwardly, the finger 112 may land either between two adjacent teeth on one tape or upon the upper surface of an individual tooth, as shown in FIG. 7. As the pressure pad 72 continues to descend, the bar 104 guided in the inclined passage 102 will travel slightly towards the left, as viewed in FIG. 7, against the action of the spring 110. As it does so, the finger 112 eventually finds the space 114 adjacent the tooth upon which it landed and the finger drops into the space 114, and as the presssure pad still continues to descend, the bar'l04 moves upwardly relative to pad 72 and the entire chain 32 below the punch 78 is pulled leftward by the finger. Although the entire vertical travel of the pressure pad 72 is relatively small, the pressure pad still continues now to travel downwardly until the projections 74 abut against the tapes 48, thus arresting further downward travel thereof and also thus arresting further pull of the chain 32 by the finger 112. At this instant, the position of the chain will be as shown in FIG. 8, that is one edge of one tooth is aligned with the end edge of the punch 78, so that as the punch continues to advance further towards the position shown in FIG. 9, it will out clean a full end tooth 52a in alignment below the end edge of the punch, and the latter will pass the adjacent tooth 52b without cutting it partly or otherwise damaging it. It will be noted that the finger 112 engages the teeth on one tape only and is accordingly on one side of the punch 78. lt will be further noted that the lower edge of the punch 78; is arcuate or angled, so as not to cut all the teeth at the same instant, which would require a greater force at such a moment.

As the punchdesccnds, it enters a space 136 between the inserts 62, thus cutting the teeth against the cutting edges of the inserts.

When the cutting edge of an insert becomes worn, the ,screws 66 are loosened and plate 64 lifted. The insert'is then rotated through thus presenting a new cutting edge to the punch. Thus, by turning the insert four times, four new cutting edges are presented. If the length of each insert is at'least twice the length of the cutting edge of the punch, the insert may also be turned thereafter end-to-end and is then available again for four one-fourth turns, presenting each time a different cutting edge to the punch, and thus resulting in a total of eight cutting edges for each insert.

It is understood that a plurality of fingers may be used instead of only one finger on the sliding bar 104 so as to engage in a number of spaces 114. It is further to be understood that the active length of the punch 78 is predetermined to be exactly equal tothe distance between a predetermined number of teeth so that a similar clean cut is provided at the opposite end of the gap 138 formed by the machine in the slide fastener chain 32.

It will be understood that each of the elements described above, or two or more together, may also finda useful application in other types of gapping machines for slide fastener chains differing from the types described above.

While the invention has been illustrated and describedas embodied in'a gapping machine for a slide fastener chain provided ,with means for properly aligning the position of the teeth on opposite ends of the gap to be formed in the chain with end edges of the punch, it is not intended to be limited to the details shown,

since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully I reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning andrange of equivalence of the following claims.

What is claimed as new and desired to be protected by letters Patent is set forth in the appended claims:

1. In a machine for punching out interlocked teeth carried on adjacent edges of a pair of tapes of a continuous slide fastener chain toprovide in the latter gaps free of teeth, a combination comprising die means having an upper surface; punch means arranged above said upper surface of the die means and including a pressure pad formed with a slot therethrough and a bladeshaped punch extending through said slot, said pressure pad and said punch being movable relative to each other and toward and away from said die means in such a manner that during movement of said pressure pad and said punch toward said die means a slide fastener chain portion on said upper surface will be clamped on the latter by said pressure pad whereafter said punch will punch out interlocked teeth from the chain to form a gap therein; and means carried by said pressure pad for aligning longitudinally the teeth on said chain relative to said punch so that said punch will punch out complete teeth on opposite ends of said gap without damaging adjacent teeth on the opposite ends which are to remain on the slide fastener chain.

2. A combination as defined in claim 1, and including a punch holder block carrying said punch and arranged above said pressure pad, means connecting said punch holder block and said pressure pad for limited movment relative to each other in the direction toward and away from said die means, and biasing means for biasing said pressure pad away from said punch holder block and towards said die means.

3. A combination as defined in claim 2, wherein said connecting means comprise pins fixed to said pressure pad and projecting upwardly therefrom normal-to said upper surface of said die means through bores in said punch holder block to be slidably guided therein, and

cooperating means on said pins and bores for limiting movement of said pressure pad away from said punch holder block, said biasing means comprising compression springs between said punch holder block and said pressure pad.

4. A combination as defined in claim 2, wherein said blade-shaped punch has a pair of end edges substantially normal to said upper surface of said die means, and wherein said aligning means is arranged adjacent one of said end edges of said punch for aligning a side face of one tooth with said end edge when said pressure pad engages said chain portion.

5. A combination as defined in claim 4, wherein said aligning means comprise a bar carrying at the lower end a finger of a width substantially equal to the space between adjacent teeth on one tape of the slide fastener said die means, and means limiting downward movement of said bar relative to said pressure pad.

6. A combination as defined in claim 4, wherein said aligning means comprises a passage formed through said pressure pad extending inclined to the vertical with the upper end of said passage spaced further from said end edge of said punch than the lower end thereof, a bar slidably guided in said passage and having at a lower end thereof a finger projecting downwardly beyond said pressure pad and having a width substantially equal to the space between adjacent teeth on one tape of the slide fastener chain, said bar being formed with an elongated slot extending in longitudinal direction of said bar and having opposite closed ends, a pin fixed to the pressure pad and extending transversely through said slot in the region of one of said ends, and a compression spring in said slot between said pin and the other end of said slot.

7. A combination as defined in claim 1, wherein said die means comprises a pair of spaced apart die blocks and a pair of elongated straight inserts of square crosssection releasably secured to said die blocks to partly overlap the space between the spaced apart blocks in such a manner that opposite side faces of said inserts are spaced from each other a distance substantially equal to the width of said punch so that the upper edges of said opposite side faces of said inserts form cutting edges cooperating with said punch for punching out teeth on said slide fastener chain portion during movement of said punch between said cutting edges, whereby when said cutting edges are worn, fresh cutting edges may be presented by tuming each of said inserts through 8. A combination as defined in claim 7, wherein the length of each insert is at least twice the length of said punch so that each of said inserts may also be turned end-to-end and then again be turned through 90 each time.

9. A combination as defined in claim 7, wherein said inserts are made from hardened steel.

10. A combination as defined in claim 7, and including a pair of guide means connected to said die blocks for guiding a slide fastener chain in longitudinal direction, one of said guide means being provided with means for the scraping off portions of punched out teeth still clinging to the tapes. 

1. In a machine for punching out interlocked teeth carried on adjacent edges of a pair of tapes of a continuous slide fastener chain to provide in the latter gaps free of teeth, a combination comprising die means having an upper surface; punch means arranged above said upper surface of the die means and including a pressure pad formed with a slot therethrough and a blade-shaped punch extending through said slot, said pressure pad and said punch being movable relative to each other and toward and away from said die means in such a manner that during movement of said pressure pad and said punch toward said die means a slide fastener chain portion on said upper surface will be clamped on the latter by said pressure pad whereafter said punch will punch out interlocked teeth from the chain to form a gap therein; and means carried by said pressure pad for aligning longitudinally the teeth on said chain relative to said punch so that said punch will punch out complete teeth on opposite ends of said gap without damaging adjacent teeth on the opposite ends which are to remain on the slide fastener chain.
 2. A combination as defined in claim 1, and including a punch holder block carrying said punch and arranged above said pressure pad, means connecting said punch holder block and said pressure pad for limited movment relative to each other in the direction toward and away from said die means, and biasing means for biasing said pressure pad away from said punch holder block and towards said die means.
 3. A combination as defined in claim 2, wherein said connecting means comprise pins fixed to said pressure pad and projecting upwardly therefrom normal to said upper surface of said die means through bores in said punch holder block to be slidably guided therein, and cooperating means on said pins and bores for limiting movement of said pressure pad away from said punch holder block, said biasing means comprising compression springs between said punch holder block and said pressure pad.
 4. A combination as defined in claim 2, wherein said blade-shaped punch has a pair of end edges substantially normal to said upper surface of said die means, and wherein said aligning means is arranged adjacent one of said end edges of said punch for aligning a side face of one tooth with said end edge when said pressure pad engages said chain portion.
 5. A combination as defined in claim 4, wherein said aligning means comprise a bar carrying at the lower end a finger of a width substantially equal to the space between adjacent teeth on one tape of the slide fastener chain, means mounting said bar on said pressure pad movable in a direction inclined to the vertical with the upper end of said bar spaced further from said end edge than the lower end thereof, means biasing said bar relative to said pressure pad towards said upper surface of said die means, and means limiting downward movement of said bar relative to said pressure pad.
 6. A combination as dEfined in claim 4, wherein said aligning means comprises a passage formed through said pressure pad extending inclined to the vertical with the upper end of said passage spaced further from said end edge of said punch than the lower end thereof, a bar slidably guided in said passage and having at a lower end thereof a finger projecting downwardly beyond said pressure pad and having a width substantially equal to the space between adjacent teeth on one tape of the slide fastener chain, said bar being formed with an elongated slot extending in longitudinal direction of said bar and having opposite closed ends, a pin fixed to the pressure pad and extending transversely through said slot in the region of one of said ends, and a compression spring in said slot between said pin and the other end of said slot.
 7. A combination as defined in claim 1, wherein said die means comprises a pair of spaced apart die blocks and a pair of elongated straight inserts of square cross-section releasably secured to said die blocks to partly overlap the space between the spaced apart blocks in such a manner that opposite side faces of said inserts are spaced from each other a distance substantially equal to the width of said punch so that the upper edges of said opposite side faces of said inserts form cutting edges cooperating with said punch for punching out teeth on said slide fastener chain portion during movement of said punch between said cutting edges, whereby when said cutting edges are worn, fresh cutting edges may be presented by turning each of said inserts through 90*.
 8. A combination as defined in claim 7, wherein the length of each insert is at least twice the length of said punch so that each of said inserts may also be turned end-to-end and then again be turned through 90* each time.
 9. A combination as defined in claim 7, wherein said inserts are made from hardened steel.
 10. A combination as defined in claim 7, and including a pair of guide means connected to said die blocks for guiding a slide fastener chain in longitudinal direction, one of said guide means being provided with means for the scraping off portions of punched out teeth still clinging to the tapes. 